Termites: signs, protection systems and inspections
Subterranean termites reach timber from the ground, usually unseen, through mud tubes, cracks and anything that bridges the inspection zone. Signs include mud tubes on stumps, walls or slab edges, timber that sounds hollow or crumbles, mud packed into cracks or joints, and swarms of winged termites. No system stops termites reaching a site; protection relies on a barrier or monitoring system, an inspection zone kept visible, and inspection at least every 12 months. In newer homes a durable notice, usually in the meter box, records the system installed.
- 01SystemA barrier or monitoring system around the building
- 02ZoneA visible inspection zone, kept clear of soil and paving
- 03InspectA licensed inspection at least every 12 months
No system stops termites reaching a site. Inspection is what catches them.
Signs of termite activity
| Sign | Where | What to do |
|---|---|---|
| Mud tubes, about pencil width | Stumps, piers, walls, slab edges, behind cladding | Do not break them; arrange a licensed timber pest inspection |
| Hollow-sounding or crumbling timber | Skirting, architraves, door frames, floorboards, decks | Leave it undisturbed for the inspector |
| Mud packed into cracks or joints | Plaster cracks, cornices, timber joints | Note the location and arrange inspection |
| Swarms of winged termites | Around lights and windows on warm, humid evenings | Collect a few if you can; arrange inspection |
| Sagging floors or jamming doors and windows | Throughout | Rule out termite damage alongside other causes of movement |
Disturbing an active nest or workings can drive termites elsewhere in the building and make treatment harder. Leave suspected activity alone and get it inspected.
Conditions that invite termites
| Condition | Why it matters | Fix |
|---|---|---|
| Soil, mulch or garden beds against walls | Hides entry and bridges the inspection zone | Keep the slab edge or wall base visible |
| Paving laid over the slab edge or weep holes | Termites can enter unseen beneath it | Keep paths at least 75 mm below the termite barrier |
| Leaking pipes, hot water overflows or air-conditioner drips | Moist soil attracts termites | Fix leaks; drain overflows away from the house |
| Timber in contact with the ground | A direct food source and pathway | Remove or isolate timber, sleepers and stored wood; check deck posts and sleeper walls |
| Poor subfloor ventilation | Damp timber is more attractive and decays | Clear vents; see the subfloor guide |
| Stumps of old trees near the house | A common nest site | Have them inspected; consider removal |
The path and clearance rules come from QBCC's maintenance guide. For raised floors, the clearance and ventilation numbers are in subfloors, stumps and restumping.
How termite management systems work
The ABCB Housing Provisions make the key point plainly: a termite management system will not stop termite activity on a site. Its job is to stop termites entering the building unseen, forcing them into the open where an inspection can find them. Its effectiveness relies on regular maintenance and competent inspection.
| Type | How it works | What it needs |
|---|---|---|
| Chemical soil barrier | Treated soil around and under the building deters or kills termites | Periodic re-treatment; some use reticulation pipes for top-ups |
| Physical barrier | Stainless steel mesh, graded stone or termite shields block concealed entry | An intact barrier, not bridged by later work |
| Baiting and monitoring | Stations around the house detect activity and deliver bait to the colony | Regular servicing to the provider’s schedule |
| Inspection zone | A visible strip, such as an exposed slab edge, where tubes can be seen | Kept clear of soil, paving and garden beds |
Find the durable notice
Where a termite management system is required in a new building, a durable notice must be permanently fixed in a prominent location, such as the meter box, recording the system used and advising that it should be inspected and maintained. Look for it in the meter box, and sometimes in a kitchen cupboard. If it is missing, faded or out of date, ask the vendor or owner for treatment records, and have a licensed technician confirm what is installed.
How often to inspect
Most termite management systems need a licensed pest controller to inspect and service them at least every 12 months, more often in high-risk areas. Inspections of existing buildings follow AS 3660.2, and pre-purchase timber pest inspections follow AS 4349.3. Read the timber pest report alongside the building report, as described in how to read a building and pest report.
Common misreads
| What people say | What is closer to right |
|---|---|
| "The house is on a slab, so termites cannot get in" | Termites can enter through slab edges, joints and penetrations. A slab alone is not a complete system. |
| "It has a barrier, so I do not need inspections" | Barriers can be bridged or expire. Inspection at least every 12 months is what catches activity. |
| "Double brick houses are termite-proof" | Roof framing, floors, door frames and joinery are usually timber. |
| "I sprayed the mud tubes, so they are gone" | Surface sprays can drive termites elsewhere. Professional treatment targets the colony. |
| "No activity found means no problem" | A report can find no activity and still list serious conducive conditions. Fix them. |
Worked example: a new garden bed and an old notice
Illustrative reasoning example, not an inspected property. A 2008 brick-veneer house on a slab has a durable notice in the meter box for a chemical barrier, last treated in 2015. A new garden bed now covers the slab edge along one side.
The record shows a system was installed, not that it is current. The garden bed has buried the inspection zone. The next steps are to pull the bed back to expose the slab edge, have a licensed technician inspect and advise on re-treatment, and update the notice and records. See keeping a record of your home.
Frequently asked questions
What are the signs of termites in a house?
Mud tubes on stumps, walls or slab edges, timber that sounds hollow or crumbles, mud packed into cracks or joints, sagging floors or jamming doors, and swarms of winged termites on warm, humid evenings.
How often should a house be inspected for termites?
At least every 12 months, and more often in high-risk areas. Most termite management systems require a licensed pest controller to inspect and service them at least annually.
What is a termite durable notice?
A permanent notice fixed in a prominent place, usually the meter box, recording the termite management system installed and advising that it should be inspected and maintained. It is required where a system is required in a new building.
Do termite barriers stop termites?
Not entirely. A termite management system does not stop termite activity on a site; it stops termites entering the building unseen so inspections can detect them. It relies on maintenance and regular inspection.
Should I spray termites I find?
No. Disturbing or spraying them can drive termites elsewhere in the building and make treatment harder. Leave them alone and arrange a licensed timber pest inspection.
Can houses on a concrete slab get termites?
Yes. Termites can enter through slab edges, joints and service penetrations, especially where garden beds or paving cover the edge. A slab is not a complete termite management system on its own.
Which standard covers termite inspections of existing homes?
AS 3660.2 covers termite management in and around existing buildings, and pre-purchase timber pest inspections are carried out to AS 4349.3.
How this guide was researched
We start from visible signs, list the conditions that invite activity, explain what each system type can and cannot do, and show where to find the installation record, with a fictional example.
Limits: Termite risk varies by region and species. Only a licensed timber pest inspection confirms activity or damage.
Sources
- Housing Provisions Part 3.4: Termite risk managementAustralian Building Codes Board · accessed
- AS 3660.2:2017 Termite management, Part 2: In and around existing buildings and structuresStandards Australia · accessed
- Your essential home maintenance guideQueensland Building and Construction Commission · accessed
- Building Technology Resources (foundation maintenance, condensation, managing termites, asbestos)CSIRO · accessed
- Protect against termitesQueensland Building and Construction Commission · accessed